Most existing motors are assembled with an electric starter. As shown in FIG. 1, a main shaft 1, a drive gear mechanism 2, a shift fork 3, an electromagnetic relay guide rod 4 and a first return spring 5 are arranged in a housing of the electric starter. The electromagnetic relay guide rod 4 moves rightwards, which promotes the shift fork 3 to rotate clockwise around a hinge joint A. An upper end of the shift fork 3 compresses the first return spring 5, and a lower end of the shift fork 3 enables the main shaft 1 to move leftwards so that the drive gear mechanism 2 engages with a flywheel gear 6 of a motor. Then, the main shaft 1 promotes the flywheel gear 6 to rotate at a high speed. However, when the motor needs to be turned before work, the flywheel gear 6 is required to rotate at a low speed, but an existing electric starter can only realize high-speed rotation of the flywheel gear 6 and does not have a manual turning function.
Traditional electric starters do not have the manual turning function. During detection and maintenance of a motor, a flywheel gear of the motor can only be levered to rotate by means of a steel crowbar. Although low-speed precise rotation can be realized, there are potential safety hazards (for example, if an operator forgets to take down the steel crowbar, the steel crowbar might be popped out when the flywheel gear of the motor rotates, which will cause casualty or equipment malfunction), and efficiency thereof is low.